Your brain goes through cycles at night, falling into deep sleep and then stirring after an hour or so before dropping off again. These apps aim to wake you in the morning during light sleep, so you feel refreshed.

Sleep Cycle recommends placing your phone face down between the mattress and bottom sheet, next to your pillow, to monitor you as you toss and turn. If you share a bed, place the phone on your side rather than in the middle. You'll need a power point near the bed so your phone can charge while you sleep, and there's a sensitivity test to ensure you've placed it correctly.

Meanwhile SleepBot recommends placing the phone face down next to your pillow, but not under bottom sheet, so it might get knocked off the bed. You can adjust the sensitivity, but there's no calibration test. Both apps chart your sleeping patterns but SleepBot adds audio tracking and sound recording, which you can use in conjunction with motion tracking or instead of it.

SleepBot chooses the best time to wake you within a 30-minute window, so set the alarm for 7am and it could wake you as early as 6.30am. Sleep Cycle lets you set a window of 10 to 90 minutes.

Both apps let you choose from a range of gentle alarm sounds, or else a music track. You snooze the Sleep Cycle alarm by tapping the back of the phone, granting you a few minutes reprieve. Snooze times get shorter until you reach alarm time, when snooze is disabled. Turning off the alarm requires swiping a small slider.

You need to turn over your phone and touch the bottom of the screen to snooze SleepBot's alarm, which is cumbersome when you're only half awake. Swiping up turns off the alarm, which is easier to do accidentally than disabling Sleep Cycle's alarm.